A suburb is a mixed-use or residential area, existing either as part of a city or urban area or as a separate residential community within commuting distance of a city. Suburbs might have their political jurisdiction, especially in the United States, but this is not always the case, especially in the United Kingdom where suburbs are located within the administrative boundaries of cities. In most English-speaking countries, suburban areas are defined in contrast to central or inner-city areas, but in Australian English and South African English, suburb has become largely synonymous with what is called a "neighborhood" in other countries and the term extends to inner-city areas. In some areas, such as Australia, India, China, New Zealand, the United Kingdom, and parts of the United States and Canada, new suburbs are routinely annexed by adjacent cities. In others, such as Morocco, France, and much of the United States and Canada, many suburbs remain separate municipalities or are governed as part of a larger local government area such as a county. In the United States, beyond the suburbs are exurbs, or "exurban areas", with less density but linked to the metropolitan area economically and by commuters.